Measuring "Scope-Height-Above-Bore"

Dmay

Dmay

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When measuring scope height above bore, to enter into a ballistic program, and assuming an aggressive rail, (45 MOA in my case), where is the proper place to take the measurement? At objective end? At the turrets? What would the reasoning be?

I know, I know, it won't make enough difference to matter, but it's just one of those things I get to wondering about when I wake up in the middle of the night....
 
Measure the objective bell diameter and divide by two, then add that to the bottom measurement. Sorry, I read your question too quickly and overlooked your point, being the impact of the cant of the scope. Interesting question.
 
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I am using Strelok Pro for several years and this how I doit, also people on all forums agree about:
- always shall measure the "scope height" at the windage/elevation mechanism box (or closest point), especially you have a 45 MOA mount.

btw, I never saw 45 before, I have several mounts in 10 and 20 MOA. Is that a side mount?
 
If you do the math, the total cant on a 12" long scope angled at 45 moa is 0.15". So if the centre is the measuring point, you could measure the objective and subtract half that.
 
measure your bolt shaft diameter (under the eye piece), divide by 2
measure your eye piece, divide by two
measure from top of bolt shaft to bottom of eye piece.

add all together and that's your height over bore.

Boltgun
 
I would assume that measuring from the middle of your front ring to the center of the bore about as accurate as its goin to get! This is how Ive done it and it seems to work on the ballistic apps Ive used. Its so simple that even I can do it!!
 
In reality, even with the canted rail, the difference would be marginal. However, the true measurement should take place where the adjustment will happen, which is at the turrets.
45 moa is 0.75°, so like I said before, marginal.
 
Grizzlypeg said:
I can't say the answer is correct, but according to chatgpt, a 1/8" measuring error in scope height would result in an error of 1.25" at 1000 yards....
Click to expand...
A scope height measuring error of 1/8 can easily throw you out of paper even @ 100 especially :)) sepend how big of a ring you aiming).
And there are also two other very important misalignments in either vertical or horizontal plane.
 
bigHUN said:
A scope height measuring error of 1/8 can easily throw you out of paper even @ 100 especially :)) sepend how big of a ring you aiming).
And there are also two other very important misalignments in either vertical or horizontal plane.
Click to expand...
Can't say I agree, or even understand what you are referring to. This discussion is about correctly measuring the height of a scope above the bore, for the purposes of ballistic calculations of compensation for drop at various distances. Please elaborate. Assume someone has sighted in the scope. How does not knowing, or not knowing correctly the height of the scope above the bore induce any error at the sighted in distance? It can only affect balistic extrapolations to other distances, and the difference an 1/8" error in scope height does little to that calculation.
 
Center of scope tube between rings.
I don't wake up thinking that. More like can I hold it till morning or do I get up and let it go.
 
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Measure objective diameter and divide by 2, then add gap above barrel, then barrel diameter at same section and divide by 2 and add to the sum of the first two. This is easiest place to get measurements from
 
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